MUCEDIXES. 



605 



1817. 



Oidiuzn concentricum. 



Oidium." 



B. <5' Br. " Concentric 



Tufts delicate, maculfefonn, rounded, scattered, sometimes 

 confluent ; flocci erect ; spores straight, large, fusiform, greyish- 

 white. — B. 4' Br. Ann. N.H. no. 547. C^Iindrosporium concentri- 

 cum. Ung. Exan. t.2, f. 9. Fusisporiumurticce. Desm. exs.no. 

 230. Ann. Sc.Nat. (1838), x.j9.309. 



On leaves of various plants. 



Variable. In all the forms we believe that tbe threads protrude throu,^h 

 the stomata. Amongst the spores some occur which are large and unisep- 

 tate. It is possible that after the spores fall they may increase in size. — 

 B.SfBr. 



OiDiuM MOXiLioiDEs. Lk. See Erysiphe graminis. 



OiDiuM TUCKERi. B. Gard. Chron. 1847, p. 779. Ann. N.H. 

 no. 544. 



OiDiuM ABORTiFAciENS. B. Ann. N.H. no. 545. Ergotetia 

 abortifaciens Quekett. See Claviceps purpurea. 



OiDinji BALSAMii. Mout. B. ^^ Br. Ann. N.H. uo. 763. Gard. 

 Chron. Ap. 15, 1854, on Verbascum nigrum and strawberries. 



OlDIUM ERYSIPHOIDES. Fr. 



OiDiuii LEUCOCONIUM. Desm. Berk. exs. no. 100. See Sphce- 

 rotheca pannosa. 

 These are all conidiophoroua conditions of other fungi. 



Gen. 237. 



STYSANUS, Corda. 



Stem erect, carnoso-cellulose, apex ex- 

 panded into a hemispherical or cylindrical 

 head ; spores simple, apiculate at each 

 end, connate in simple or branched moni- 

 liform threads. — Corda. Icon. i. p. 22. 



{Fig. 272.) 



1818. 



Corda. 



Stysanus stexnonitis. 



" Clavate Stysanus." 



Gregarious ; stem simple, slender, 

 brown-black, fibrous, ending above in a 

 cylindrical head of spores ; threads of 

 spores slightly branched, glaucous ; spores 

 oval, concatenate, glaucescent, diapha- 

 nous, often with a solitary nucleus. — 



Corda. Icon. i. /. 283. Fckl. exs. no. 175. Periconia stemonitis 



Pers. Syn, t. 3,/. 15. 



Fig. 272. 



